I just bought a 881 also. I needed to replace my Grandpa's Mossberg Model 45B (70 year old varmint rifle). I looked around at the new 981T because I like the tube fed bolt action. I did learn during my search that the 881 is not compatible with the three types of 22 rounds, only the LR. Who cares...I can't remeber last shooting 22 shorts and from what I hear, the 22 longs aren't real popular anymore. So 22LR it is.
I paid $140 for mine, but from the action and wear patterns, this gun is like new. Mine is a 1995 model and I like the wood stock versus the poly stock on the 981T. I have tried to seek out info on the gun, and have received the owners manual from Marlin...they got me a copy in about a week.
Congrats on your purchase!