Are you looking for a two stroke specifically?
NSR's come in several models, from the MC16 to the MC28.
MC16's are now ancient and probably not worth buying if you want to ride it a lot (lack of parts). Look very old, and aren't that powerfull.
The 18 is next oldest, and there are some great ones knocking about. They were unrestriced, and many believe they make the most power of all the engines as they have better porting than the later models. Expect high fifties stock. Starting to look dated and again, parts becoming rare.
From about 1990 onwards the MC21 was produced, and was restricted by Jap laws to 45hp. Fairly easy to overcome, and unrestricted will show around 60hp. A better chassis than the 18 (easier to work on for starters) and much more modern looking with the gull arm. Parts still pretty good, and lots owned so advice and help easy to come by.
MC28 appeared mid nineties, and has a single sided swing arm. More drastically restricted, and a lot harder / more expensive to de-restrict, though have the kudos of a 'smart card' to start them, instead of a key. Looks very modern still, expecially with a decent paintjob.
Prices range from £500 for a doggy, to almost £5000 for an immaculate MC28. Most worth buying sit between £1000 and £2000, and really condition not age or milage should be the defining factor.
Have a good read of the model history and intro, as well as the specs to get a good feel for the bikes.
Feel free to come back and ask for more info if you can't find it.
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MC21SP Plaything
BMW F800GS Bumblebee
Triumph 9551 Daytona Big boys toy
FJ1100 Sporting relic
GTS1000 oddball
