Give me the chicken and biscuits on a 54r ak or variant. For my high power cartridge I currently have an ar10 but with ammo prices the way they are and me being busier than ever I'm debating trading it off for a 7.61x54R ak. I just want to shoot, I'm done chasing sub moa.

Anyways from what I understand the veprs are single stack? Do the double to single stack 20rnd taper mags work? What's highest cap not including belt fed?

Do they (at least the veprs) take "standard" ak furniture?

54r ain't cheaper these days.
No experience with the Veprs myself, I just know 54r has been getting harder to find and more expensive before this "pandemic"

To my knowledge there is no double stack 54R Vepr mag, the largest capacity I know of is 10 rounds. The nature of the rimmed cartridge is the reason for the lack of double stack.
On the furniture front, it depends on which Vepr model you have.

There's not a factory one.

You can convert a VEPR to take Lahti M26 mags without too much effort.   I have refrained from doing this on my unfired one after the imports were cut off.  Its actually annoying, since I bought it for blasting, then the prices on them more than doubled, and mine was still unfired.

It sounds to me like you need to keep your eyes out for a WW AK-54R which is basically just a 16" PSL. They come up used from time to time. Last time I saw one the price was less than a VEPR or PSL and frankly look more fun..

Big fan of my VEPR in 7.62x54r.

CSSpecs makes very sturdy and reliable steel 10 round mags.

They don't take standard AK furniture. I have Rhineland Arms furniture on one of my VEPRs, and really like it. Ironwood also makes nice VEPR specific furniture, but theirs is a good bit more expensive.

This is the 20 round mag of which I speak.

Mancat yes exactly. Is there WW single or double stack?

The WW magwell is for the PSL magazine because it's a cut down PSL, and the Vepr should not fit it

As mentioned Veprs take their own furniture, particularly with the radius cut of the most common type of receiver, so if you are chasing the classic SVD look you won't quite get there, but they can still look good and be very functional. The WW in the photo above has a pretty rare plate on the back of the receiver that converts the back end to standard AKM furniture. Most Veprs don't have that though, they have a slant cut / radius type cut which means you can only use those types of Vepr stocks. There are some adaptors out there but WW is probably the best overall because it's riveted in place and looks pretty natural

The PG is standard AKM but the handguards only take Vepr pattern furniture and many Veprs don't have the ability to use AKM style gas tubes

I have two Veprs in 54R. A 20" barrel and a 23" barrel. Personally I don't mind the thumbhole stock they come with, super comfortable. I bought a bunch of Cspecs 10 round mags and picked up two extra extractors from a member on AK Files.