DIY pre-rinse faucet for commercial sink?

I'm just about to attach this to the wall and seal it in place. Problem is I don't have a pre-rinse which is required to clean out kettles. Those faucets are heavier and much more expensive utilizing a 3/8" NPT fitting in the center of the faucet instead of a light duty swivel type connection for a faucet made in some odd, probably proprietary plumbing size. Having it machined out of a chunk of metal is too costly. I paid too much for this faucet, I think $60, not lead free and really a piece of junk in feel. A quality pre-rinse usit is quite expensive and have gone way over budget. It's about $200 minimum to get myself a pre-rinse base with simple faucet attached. Right now I'm trying to find a pre-rinse base and buy or make the pre-rinse as I can afford it, as well as be sure it fits in the workspace. There is a cabinet 18" above the stainless section of backsplash.
Anyone engineered a way to put a pre-rinse "tee" or other fitting onto the faucet swivel attachment? It doesn't need to be industrial duty, I'll be the only one using it. I've spent nearly a month searching but maybe I don't know the correct search terms and just need a fresh idea. Person that sold me the sink and faucet said it can't be done.

My cold water line is split, kettle filling water will be filtered and be dispensed through a stainless valve. No permanent solution at this point other than the valve terminated on PEX line tied to the end of the drainboard.
I want either GHT or quick connect on both the wash faucet and filtered water faucet.
I can cut and weld stainless - simple stuff. For something more elaborate I have been calling in too many favors lately with machine shop friends to have something so odd created.

Found a pre-rinse base on eBay. After I confirm it has 3/8" pipe outlet will be able to put something together or just buy the "add a faucet" option then put something on the top for washing kettles and fermenters.

Have't had much luck finding a compact faucet for filtered water with GHT which will mount to backsplash. More control over flow rate than a 1/4 turn valve offers is preferred.

I'm pretty much in the same position. I've been using a small garden hose on the current faucet, but it gets soft in hot water and easily kinks.

BBBF, I found something at a garage sale which might work for your application. A shower head hose. They usually have a chrome or stainless jacket, designed not to kink. I would imagine the best are not designed to handle 140 F (that's what commercial pre-rinse lines are rated at), but they should be an improvement over braided hose or cheaper.
Here is an 8' one which states 1/2" connections - looks to be parallel thread which seals with a washer?http://www.amazon.com/Stainless-Handheld-Shower-Inches-Meters/dp/B004XHYNEK/ref=sr_1_1?ie=UTF8&qid=1432562719&sr=8-1&keywords=shower+hose

There is one from Delta that has a higher Amazon sales ranking. Not sure what that does as far as the warranty goes. May need to buy from authorized reseller.
As far as warranties go, Moen has always treated me right on replacement parts (free replacement parts and shipping). I hear Delta has the same policy. Chinese brands from Home Depot and Lowes are disposable, if you get a leak it goes in the landfill and they may give you a new one if you hold on to your receipt. If I remember right, commercial products such as T&S Brass, Fisher... they warranty for one year in a professional environment but NO warranty for home use. I hope the build quality is high enough where it is not an issue.

I'm not out to support Amazon in my link suggestions, it is just an easy way to search. Buy local when possible.

Thanks for the suggestion.