I'd be surprised if, after investing in a replacement head, freshening it for reuse, buying and installing the whole new timing system, fixing any piston damage, and getting the new head hardware (and specialty tools to install it), plus your time, blood, and aggravation, I doubt you'd really make anything off of it. I think if anything you'd be better off keeping it to drive yourself - that way I think you'd get a lot more return for your investment.

 

For a used, junk yard motor you can expect to spend in the neighborhood of $1200 - $2500 deprending on the condition of the motor. Just remember that some things you are going to want to take care of prior to installation of the "new" motor is to replace the oil pump/pick-up, water pump, thermostat, t-belt and tensioner. As long as you are at it you will probably want to replace coolant lines and possibly clutch components. It's much easier to do these tasks with the engine out of the vehicle, during re-assembly. And then after doing all this work... you are probably going to want to keep the car and get some enjoyment out of it. If you do plan on selling it, keep your receipts and maybe a couple of photographs to show your prospective future buyer that the work has been accomplished. This will aid your resale value. Just a few thoughts!

 

Just saw an ad in the classifieds here, guy selling two full motors. Just FYI!

EDIT: Just looked again, they're AEB. Nevermind

 

I bought my 99 1.8t qauttro not running, the previou owner started it up to go to work and the timing belt broke at idle.... so no damage to the piston heads. (only 12 valves bent)
my 99 had 130,xxx miles.... i paid more for my car then anyone will agree with but the overall condition of my interior AND exterior were miraculous.. seriously next to perfect it was a single owner car he was a none smoker not married no kids... so i mean it was perfect.

i was able to rebuild my head, with all new internals... talking all 20 valves new i mean if im alread there why not replace it all and make a brand new head?? new valve guides. i pulled cams from a newer 1.8t from a beetle so a AWP comparred to my AEB engine code.. the AWP is also a 20 valve so the cams and lifter were the same actually a little better because the AWP is a 180 hp motor comparred to the AEB which is 150 hp.
i also replaced the cam chain AND tensioner.. new head bolts, new coolant hoses new coolant t-flang new clamps.. every bolt and clamp i removed i replaced.. new timing belt and tensioners new drive belts coolant flush with new thermostate and new ect sensor new o-rings new spark plufs got coil packs from an s4 and oil change and i got the head cleaned by a machine shop when i had it tore done and new pollen filter and a carbonio intake and i only spent $1500 ish then i bought new headlights and an rs-4 front bumper and still didnt spend over $4.200 with buying the car and rebuilding the head

you can rebuild the head for cheap.. probably cheaper then buying a new motor and you will also come out with a brand new head and also with taking the head off to rebuiild you can inspect the pistons sand whatever dents they may have and clean what ever carbon build up they might have. so you will also know the condition of the bottom half of the motor.