Nsap,
I wouldn't count on finding a used pump for cheap, they're worth what they're worth and the chugger price is already about as low as they go for a 120v. There are some much cheaper 12v and 24v options that will work just fine; a side benefit is that you can power then from a small solar panel if you're interested in that kind of thing...
I have some random left-over TC Ferrules, NPT to TC fittings (you'd screw the electric elements into one of these), and some contactors and probably other random items from my electric build if you're interested in those. -I'm a HUGE fan of brazing or welding in a TC fitting and then connecting and disconnecting the electric elements via TC connectors, myself.
The elements are cheap and readily available --but if you're going to go the TriClamp connector route just be aware that the ripple elements only work with the thinnest thin wall TC ferrules and you'll probably want the fold-back only elements...
Adam