Too Slow '90

Just replaced the filter in my recently purchased '98. When I pulled the filter the whole airbox moved. I found that one of the bolts at the bottom was missing and one of the grommets on the top was missing. Can you get these pieces by themselves or do you have to by the whole assembly? It also seems near impossible to install/tighten the lower bolts with the airbox in place. I appreciate all help. Thanks.

Scotty3

I think these are the correct part numbers looking at the parts book:
10281487 Nut for lower retainer
12550385 Retainer (bolt/stud)
25176248 Insulator for lower mounting of air box
25098174 Seal (grommet) for upper hose to air box