Keep 5SFE instead of swap? Options

[Wizit]

Hey guys, i'm having a delima on whether I should swap out my 5SFE or keep it. The only reason is because I bought my 1999 GT from an old guy with only 50k on the engine (One owner car). Still had all of the original paperwork and receipts for everything. After taking this car about 6k miles and installing a performance clutch in there the car is running flawlessly and everything is clean so I have NO REASON to suspect any mileage rollback.

The kind of build I had in mind was just a simple turbo and enough boost to get some blow off valves going, to be honest I love everything about Celica cars and I own 3 of them. Gen 6's have such a sexy look to them and I want to have a small kick to it but not be so overtuned that I can't take it out as a DD incase of an emergency. What do you guys think about this? Since i'm not looking for any kind of 300hp boost or anything I assume that I could rebuild my 5SFE and run a little boost to it and not have an issue however I'm not afraid to say that out of all the work I have done on my Celicas, boosting the Engine is something I don't know much about so any advice/opinions are appreciated. Thanks!!!!