No, no need to "replace the motor", but be aware that the 89-97 NSRs all have the same centre crank bearing with integral seal, which is a known weak point. Having seen dozens of bad centre bearings over the years with increasing frequency and often non-existent seals [that I put down to poor fuels/ethanol content], I am overly cautious, and advise anyone else to be too. If you know the bike/history and/or owner, then it's a different story, but when effectively buying blind, you need to ask all the relevant questions.
The model in the advert is an "R5K" variant (with the correct motor!). The full designation is 1989 NSR250R5K MC18, usually just referred to as NSR250 R5K, MC18 R5K, or just MC18 Seed. (SEED is the colour scheme, based on the 1989 NSR500 race bike.)
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Andy.
NSR-WORLD.COM
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