Bad transaction from a Facebook seller
I've had a few damaged items arrive here both personal and on behalf of customers due to a lame packing job. I also have business UPS and FedEx accounts.
I'm sorry to report that even if UPS pays a claim, the payment will sadly go to the SHIPPER -- not to you, the buyer who spent the money for the part and the shipping charges and suffered the loss. It's backwards in my opinion, because you have to rely on the shipper / seller to reimburse you ... and that just doesn't happen that I've seen. They get that money too (and probably laugh all the way to the bank).
It's good you filed a PayPal claim (you have to do that within 45 days of your payment by the way or you're out of recourse). If UPS didn't yet confiscate the shipments to perform their investigation, get detailed photos of the boxes and all damage for PayPal and be relentless, cooperative and determined in your dealings with them. You're supposed to document the packing materials too but in your case that's not applicable.
When shipping anything or wanting to file a claim on damaged items, the box needs to have a crush weight certification label -- usually on the bottom -- and be sure it covers the weight of the contents.
Any UPS shipment valued at or over $1,000.00 requires the shipping party to print a special insurance form which the driver or UPS store employee has to sign. It covers you and helps any later insurance claim get processed faster.
I wish you luck and hope some of this is helpful.