spedometer cable grommet

i recently bought a spedometer cable for my 87 mustang. naturally, it didn't come with another grommet. u know the one. under the hood, its up against the firewall. anybody know where i can get one besides the salvage yard? dealership just sells the cable and grommet as a kit. don't want to shell out $90.00 for another. hate to jimmy rig it.
 
i didn't buy it. i got mine at a regular parts store. that was probly my mistake. dealership said ninety something. maybe the guy i talked to didn't know what the hell he was talkin bout. maybe i'll try calling a dealership in a different town. if anybody has one laying around(& wouldn't miss it), let me know. I'll buy it from ya