How much for a 2.0 16v longblock?

i'm guessing that my engine is hurting (probably bend valves, maybe broken woodruff key or something on the crank sprocket), although i won't know for sure until i take stuff apart on thursday. in preparation, i'll be looking for a 2.0L 16v engine to replace it. how much should i pay for one with around 100k miles (just the engine, i think i'll keep my cis-e)? any way to tell its condition if it's not installed? for that matter, how can i tell a 1.8 from a 2.0? lastly, it has been suggested that my timing belt stripped a few teeth and is slipping. if this is the case i guess i'll replace it and see what happens. is there any way to do this w/o the tensioner tool? if not, are there any local sources (pep boys, napa, etc) that would carry it, or is there another "specialty" tool that could do the job? i could really use some input on this guys, cause i'm pretty much in the dark here...