Never having had a 'jungle' stock...I am not sure about whether between the two versions, what they exactly work on.
They are not likely to be a lot different than a wood stock, in shape...and will not lend themselves to being modified. They are made of a material that I cannot fathom appreciating any kind of sanding to shape them. I believe these were made long before the concept of a 'paratrooper' model was conceived.
Even if it is the spike version, the bayonet channel likely isn't wide enough for the chubby end of a shortened bayonet. You might be able to use a router, any ugliness might be hidden by the bayonet...I would fear cracking it almost as much as what that might smell like.
I did find that I do have one paratrooper stock, but it is for a pinned barrel and won't work for you. The one on it's way has been delayed by five days, but minutes ago arrived in my nearest city, so I should have it by Monday.
You might consider looking for a Ram-Line (now Champion) stock...they are more slender at the wrist and are so lightweight they barely add to the weight of the rest of the gun. They are also very slender at the end where you can carefully grind out a channel for a bayonet, I have done it before. Unfortunately, I had to shorten the stock dramatically to work with a really screwy Chinese DB SKS. It is too short now for anything but that gun. I can't bring myself to use it since finding a gorgeous stock, and refinishing it. You will have to sacrifice wood for plastic though.
You probably can find the right stock on eBay pretty easily though. Avoid Yugos, those won't work for you...and they are aplenty right now. Study the inletting on your stock around the recoil lug area....as well as the distance it resides in, from the side... in relation to the more likely pictures you will see of that area. The most crucial area of an SKS stock is rarely photographed. It can be really tricky to get the right one, it took several attempts to find a wood stock for my first SKS, which is a short lug too. For some crazy reason, the only stock I have found that fit it properly was a blade stock....I gave in and ground my U stock ferrule into a V and put a blade on it instead of a spike.
One sure thing for a short lug is if you can find an inverted take down lever stock, which has an inletting above the inlet for the safety, right below the takedown lever. If you do find one...keep that one, modify if needed for your bayonet width, but don't alter it otherwise, those are pretty uncommon stocks, and the people who need one will hate you for even modding the bayo channel.
Then you can alter your current stock without worry of the $50 or so resell difference with a mismatched stock....which is where you are anyway.
A little patience and you can find the right one to keep it in a condition as it sits now, you could go ahead and mod your current stock to your tastes...and if you love it, keep it....without worry of ever needing to make it 'normal' again. But be forewarned, the wood used on Chinese stocks is the least forgiving wood I have ever applied sandpaper to. It is fiberous.