I think with a lot of import products you need to be aware that you'll be doing the QA and will in fact be working on the parts / product to get it to where you need it to be.
If you have the skills and the tools $280 + $3 for an unfinished pulley plus some time on the lathe or mill can still be worth it. I know this is asking a lot from a customer and maybe this particular example of a printer is not the best, i. e. it would totally be possible to manufacture this part within specs at cost, but I think the general notion still holds true.