If you are using your factory a-arms then you should be able to use those. But if you are using aftermarket a-arms then they should come with bushings. What type of k-member did you get?
New arms should come with new bushings but if you are re-using your stock arms you should pick up new bushings for them. The factory rubbers bushings leave a lot to be desired when in new condition. Yours are getting up there in years and if you are getting a K member I imagine you drive your car agressivly so they will be in fairly bad shape. Do it right the first time either way.