I find it funny how someone who's never built an engine before and clearly knows jack about engine building thinks that a quote outweigh's experience.
If you factor in the cost of the rb25, engine mounting kit, labour to install it (just so it sits in there and not yet runs) that'll cost you up to 10k alone. Let alone the rest of the powertrain, engine management system, and etc. If you do it yourself, it'll obviously be cheaper, but you'll have to know how to spin a spanner at the least lol.
Also you're display picture makes you look like a flog, which is 50% of the reason why you're getting these responses.