Local u-pull charges $200 for a complete EFI long block. I don't know where your prices are at, but I hope you don't pay too much.

I would do intake, headers and a cam swap. I hear the mag guys are using the GM 3100 valve springs. Whether or not you want to tear into the motor to do bearings/rings is up to you. Cost/time starts going up quick if you do. Heck, if you really need to shave the budget leave the stock cam/springs in there and put that money into the rear end. That 2.76 rear is going to make any backyard build a dog. I would swap to whatever the numerically highest gears are that you can stand. I daily drive my sig car but I live less than two miles from work and it's all city driving so I don't have to worry about highway rpm. With some gears and the stock cam you won't have a ton of hp, probably high 200's close to 300 but should have a lot of torq, I'd guess around 350ft-lbs. That with some gears should light the tires up nicely and give you that kick in the pants you want.