I bought a "Godspeed" intercooler from ebay for $89.99 with free shipping. The core is sized 24"x12"x3". It is a seeminly nice quality unit, no cracks in the end tanks, no bent fins and the welds are pretty decent (dunno about penetration). Its not light by any means but it was light on the wallet.
I have no idea about pressure drop but like others have said in other ebay intercooler threads, it can't be that much more than a "name-brand" one. I'll probably upgrade to a real intercooler in the future when the budget allows, probably air-to-water. For piping I was just going to get some aluminum u-bends and make my own with some alumiweld brazing rods and silicone couplers and t-clamps everywhere I use the alumiweld. I definitely won't be cheaping out on the t-clamps.
ebay auction similar to the intercooler I bought, except with $30 shipping