Garage is not that important, any garage with reasonable history can install it.
The important thing is to find a cheap, good engine. You should open the yellow
page (pieces usage section) and make a lot of call to find the engine and compare
the price, and warrenty. Then go to a Chinese garage to install.
Some scrap yard (car junk yard) also can install for you with some warranty.
To install an engine is easier than to fix an engine, and engine with this age can be
as cheap as $125.
The best know Chinese owned garage are Lujian and Fuji, which also enjoy quite controdiction opinions. They are famous best they are cheap, but some times cheap means cheap quality, sometime, not. Use you own judgement is the best bet. You can go there talk to them, stay for a while watching how they deal the client.
First thing is to find a good engine.