Can you replace the bearnings in the clutch basket in a ktm 50 pro sr,or do you have to buy a whole basket.

I dont know of any bearings in the basket. The clutch consists of the basket(drum), clutch shoes(3 of) on a centre hub and disc-spring stacks(one stack to each shoe) consisting of disc springs(that look like washers) and a bolt. All of which can be replaced seperately.
To remove undo the centre lock nut.Get the drum assembly off the crank(you'll need a puller for this). Take the shoe assembly out of the drum. Mearure the inner diametre of the drum and the outer diammetre of the shoe assembly. The difference between the 2 measurements should be between 1.50mm an 2.00 mm. If the difference is bigger you can insert a shim between the center hub and shoes up yo a maximum of 1mm shim, then you'll need to replace the shoe. Clean the disc springs and check for wear. Replace if needed.
The quickest way to mess up your clutch is to run on old oil. Change the transmission oil after a maximum of 5 hours riding. It needs about a cup full(250ml) so it is really not expensive considering a set of clutch shoes will set you back $60. Dont neglect this.