RLBL-esque suit for $500-1000

Hello all I am new here, but I have been lurking for awhile. Usually the first advice giving on these sorts of threads is too search older ones and that is what I did on google because the search function on the forum isn't the greatest.

Anyways I have worn RLBL suit as my first suit since learning about good suits and stuff and I have a particular preference for it maybe because it was my first, but I am certainly willing to try something else.

I made a thread on here earlier about fashionable/trendy suits but it didn't get any responses so I'll recap here. I am a young guy just turned 20, so I would prefer something slim, but positively fitting. I am on the range of 5'7-8" and 140-150 lbs But, that is likely due to the work of a tailor and not simply being pleased with the fit of an OTR suit right?

I am still a beginner here so correct me if I am wrong. I do not think I can get a fully-canvassed suit easily within my price range. Although I always prefer the best I can get I am just not sure if it is possible.

Anyways after scouring the threads these are the recommendations I have usually seen for budgets like mine.

Suit Supply
Thick as Thieves LA
Benjamin Sartorial
Kent Wang
BB Fitz/Milano (I haven't really done my research here to know which one I prefer)
and as always the (B&S section and eBay)

I understand a small amount about suits compared to people here, but other than that I feel like I know a moderate amount when compared to most people off this forum. Either way I know fully-canvassed is probably preferred, but because this will be my staple suit, but because I am still relatively young and my budget is low I probably will not achieve this. But, this is probably not going to be a big deal because I am sure recommendations I get here or half-canvassed/fused options will certainly be better than what most people in my age group wear such as H&M/Zara or the likes of.

Also quick question. I feel like I am in the realm between size Small and size Medium and the same goes for sportscoats/blazers and I'm assuming the same will hold true for suits. Sometimes I feel like I am a 36 other times a 38, and if it is a particularly slimfitting sportscoat I've noticed sometimes I am a 40. Anyways, because suits are more conservative I feel like I will be a 38 for the most part unless its DH or something. But my question is about R and S. If I am generally a 38, would I be more of a 38R or 38S and if I found say a RLBL suit to my liking in 38R if I am a 38S would that be a big deal or solve painlessly with a tailor and vice versa.

Thanks and sorry if my post is not organized.