Buying a CR250 1996 Honda?

So I m buying a 1996 CR250 2-Stroke Honda from a guy. Its in mint condition. The only thing he says is wrong with it is it needs to have the throttle position jet (rebuild kit) replaced? I don t even know what that is. Apparently its $30 to buy at the Honda shop and $70 for it to be replaced by them. Is it easy for it to be replaced and not a big deal?

Thanks.
Added (1). fmf gnarly pipe -
pro taper bars -
new plastics -

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