Go to CMSnl.com or partzilla.com and look up the part number and google that and you will find plenty. Or just ask ebay.
Tried all that and more. Got a note off to Motion Pro to see if they can make me some. Clutch cable is all I can find.
Found a clutch cable, talked to a couple shops and no body makes cables anymore. Still no response from Motion Pro but am sending the old cables to them anyway. It is the throttle cables I need. Everybody says do this or that and none have tried themselves. Slinky doesn't do it. That repair kit, if Motion Pro can't do it I will try the repair kit.
The clutch cables are available last time i checked , so you should be-able to get one. The throttle cables are another story though i'm afraid , been N.L.A available for a while. Have PM'd you over this.
Try this place ( link below) , there still available through them so i was informed via a rep there. https://www.motosport.com/oem-parts/yamaha/1987/srx250t-%28ca%29/handlebar-cable
Not long spoke to Shane there , said there available and quoted a price. This place has them listed ( link below) , but it's a long way to your front door =$. http://www.remarcables.com.au/searc...pc3RTZWFyY2hkNGdxcTJ2a2Y0aGJ2ZmZtMWg1MWJ2ZXg=
Cable 1- 51Y2631101 , 1x in stock https://www.cmsnl.com/yamaha-srx250t-1987_model9300/cablethrottle-1_51y2631101/#.X4jssNIzZ9N Cable 2- 51Y2631201, 1x in stock https://en.impex-jp.com/parts/new/search.html?partNo=51Y-26312-01