No my only reference to the model 597 Remington is for a 22lr semi-auto rifle.
Yes, but, expect to pay for it.
Rimfire rifle made by Remington
i bought my 597 for $200 but you could proabobly find one that's cheaper.
You will probably have to contact a barrel maker.
Do a search for Jarvis. They make a bull barrel for the $597, it runs $198 in either blued or stainless.
No. The stocks are not interchangeable. Boyds make some nice aftermarket stocks for the Remington 597 as well as the Ruger 10/22. The Ruger 10/22 has all sorts of aftermarket parts to customize the look and performance of your 10/22. The Remington 597 is just now beginning to get more aftermarket products available to customize your rifle.
Check the list of vendors on the Remington Society of America here: http://remingtonsociety.com/rsa/service
You will have to contact barrel makers or visit their web sites to see if anyone is making them or would be willing to. Jarvis makes aftermarket "Bull" barrels for the Remington 597 in .22lr, but they no longer make the .22 Magnum barrel - I bought the last one a year ago