What guitar set up to get?

Stratobagster is right on with the Mexican strat, although they cost $500 + tax and case when getting them new. The best thing to do is get that guitar on Ebay used. You also have the option of looking for a Japanese built strat which are a little better in quality than the Mexican strats, but cost a little bit mor. You can probably get a used Mexican strat for around $300 or so on Ebay. If you are savvy you can get one on Craigs list for a bit less. The key to some of the SRV and Mayer sounds are single coil pickups. A tubescreamer is a great option, but also consider the Boss Blues Driver. In either event, you may want to swap out the pickups on the strat and put in some good single coils. The lil' 59 is excellent as are Fender Lace Sensors (Blue models for your style). Check into some Duncan and Dimarzio single coils. You can snag them on Ebay for around $40 each. The Peavy amp is a good little amp, but also check into some Line 6 amps. They have some great presets, and I believe one for SRV. Fender also has some modeling amps out as well now. If you go used on most of this gear via Ebay, you will be able to get better quality stuff. Also, check into the Fender Highway strat line. They are $700 new, but can be picked up cheaper used as well.