all of those frames have vertical drop outs. Although not ideal for ss applications, it can be done by using a chain tensioner, eccentric hub, or a magic gear.
These frames might be better:
Do you know exactly what you'd like to do? Unless you have a lot of parts sitting around building up from the frame will be more expensive. You may want to look into complete bikes if "affordable" is one of your goals.
not fork. rear horizontal drops.
use the magic gear calculator.