End of story. You want to go fast? No more bullet proof motor, it's expensive, and you can't be an idiot about engines (unless you have deep pockets). And dumping a bunch of money into a 2.slow is going to get you a slightly faster 2.slow.
I think your options are realistically:
Sell it for a 1.8/VR
Swap for a 1.8/VR
Neuspeed Charger (and yeah takes power to make power but you make more power going from < 100whp to ~ 140whp is huge)
Forget about going fast and build a show car
You've made it clear you don't have deep pockets for a legit, solid, reliable turbo build. For the sake of saving your VW, don't get some cheap Chinese-made plastic turbo kit. You don't go that route for the same reason you wouldn't bungee jump with a nylon rope "just because it's cheaper"