What type of outlet do you plan to use for your 240V supply, and what kind of plug is on the Foundry cord now? The adapter you show plugs into a NEMA TT-30 outlet, but most three prong dryer outlets are NEMA 10-30, and the two are not compatible. Also, what will you be doing to get GFCI protection on the 240V circuit?
Nah, you don't need one of those (which is just a big MOV in a plastic case).
You want a GFCI breaker in that circuit, either in the panel or using an in-line GFCI cable...
That is not a GFCI. A "surge" protector is for protecting equipment from voltage spikes on the power lines. Surge protectors do nothing to reduce your chances of electrocution.
If you are installing a new circuit, you should not use the NEMA TT-30 plug/receptacle combo, as they are only approved for travel trailer/RV use. For a 30A circuit, you should use either a NEMA 10-30 (three wire) or NEMA 14-30 (four wire) plug/receptacle. Personally, I'd go with the 14-30, as you have more flexibility in what can be plugged into it. Standalone 240V/30A GFCIs are very expensive. You are better off putting a GFCI breaker in the service panel.