I've been "dialing in" a 7.5" 5.56 BCA pistol upper since December 2020.
Ran into the next issue where the ejected brass was hitting so far forward (12:00) that it would hit the ejector ramp on the outside the receiver and bounce back in the chamber or possibly just bounce around inside the upper with the bolt back until the bolt came back forward, grabbed a fresh round, and tried to push the new round and the (usually sideways) empty casing in the same space.  It was reminiscent of me trying to put on skinny jeans with both legs in one pants leg.  Not pretty.
Ok, this is overgassed.  No problem, just have to slow down the bolt.  Heavier buffer and a stronger spring.  Got a Springco red and an Odin Works adjustable buffer and built a custom buffer at about 6.4 oz.  Took it to the range, and it's now ejecting at a pretty steady 1:30-2:00.
Does anyone know of an adjustable gas block that's low profile to fit under my handguard and will handle the pressures of a pistol length gas system?  I've looked up a few; all the ones I've come across say they're not rated for suppressed or pistol length gas systems.
I'd like to get rid of the super heavy buffer and red spring and get back to an H2 or H1 so the lower will be "universal pistol" again.
Here's the specs on the upper: https://www.bearcreekarsenal.com/556-7-5-parkerized-m4-barrel-1-7-twist-pistol-7-handguard-rc.html
Obviously, this is a budget build (I'm guessing the BCA upper gave it away) so I really don't want to drop too much on this.  It's a hobby/plinker gun, so if I never get it working right, I'll still enjoy the chase.
Anyone have any good suggestions?

use the bootleg adjustable carrier

Superlative Arms

SA or Odin Works.  I have an Odin Works adjustable gb on my 8.5" 5.56 pistol.

Odin Works is the answer on a budget.  A few months back they were including them with most of their barrels.

Thanks guys - I found the Odin Works tunable lo pro gas block for under $40.  The superlative clamp on is a bit too tall on the bottom of the block where the clamp screws are.  I like the idea of the adjustable bolt carrier, but the cost is a little prohibitive on this build.  I think once I can afford getting a can, I'll definitely put in the budget for a tunable bolt carrier.

I'm expecting the Odin block soon - I'll update after I get in installed and dialed in.

Excellent price doesn't mean "budget". Odin Works steel GBs are top-shelf.

I agree.

I've been happy with my SLR rifleworks on my 7.5 blaster.