Air Venturi Any recommendations for Air Venturi Avenger Bullpup Upgrades/Accessories for a PCP Newb on a budget

I just got my first PCP rifle the Avenger Bullpup a week ago, on sale for $299 from Pyramid, and am working on a budget build.

I went with the CVLIFE 6-24x50 for $50- Amazon Link

VEVOR Hand pump for $50 - Amazon Link (Wow so much more force needed to pump than expected. My kid that weighs a little over a hundred can jump and put their full weight on the pump without fully compressing it.) Depressurizing to tune made me sad. Especially when I had to do it a second time. (I have it set to 1800 now). I backed off more than a quarter turn the first time I went to adjust and had the regulator gauge side down when filling, so I did not see what I had done till I had hand filled to 4000 :(....

Looking through the forums I found Buck Rails moderators, I am going to add to my wish list, for down the road. - Buck Rails Link
Any thoughts on Donny FL vs UNI adapter. I have not seen much info about Buck's UNI adapter for the avenger.

I have no experience with Bipods, but from what I have read and watched I see it is highly recommended that you get one for this gun. What features should I be looking at,. Below is my best guess:
Height around 6-9"
Picatinny Rail connection (bottom or side) does mlok work for side rails? One person recommended a bipod with mlok, but I don;t know if they swapped out their rails?
Is the 360 swivel and tilt nice to have or just extra weight?

Recommendations for DIY rear support for precision shooting?

I would love to get the Quick shot upgrade if it is still being made so I can move the lever forward and to the left hand side.. I see one for sale used on this site, but just joined so I can't PM anyone for until I am a member for at least 10 days.

I have seem pictures of Bullpups with a 3d printed support for the rail. Does anyone know if the 3d print file is available or is it custom order only?
Helpful 3D print Files I found while looking:
Magazines - 12 and 20 Round Magazine 3D print files
Moderator - Moderator 3D print files
Gauge Covers - Gauge Cover 3D print Files

Any Recommendations for a cheap case or bag that will fit the rifle with scope? My Plano single Rifle with scope case I have for my Gamo Swarm is too small for bullpup with scope.

Any other must haves? I am trying to keep total buy in under $500 for essentials, with scope and pump and gun I am currently at $420 which is the bare essentials.
I've got both versions of the Avenger in 25 caliber the long and the Bullpup. Very fine rifles I shoot regularly. You've made an awesome choice!
 
Personally I like sand better than rice, but you need something that is finely woven. I found rice in the sock to be too light and too coarse for a stable rear support. I have a couple old lead shot sacks that I found somewhere and filled them with sand and double-fold zip-tied the end closed. Have been using them for many many years and have won many local matches with their help. Another good bipod for the money is the Caldwell XLA. Kinda expensive when compared to the really cheapy overseas copies you can get now, but still a budget option with far better build quality. I also have a UTG bipod I like that is built really well and is very solid, I think I paid like $90.

I’m currently using this bipod too. It feels really solid, locks into place and rotates smoothly. Performs well at a good price!