Hey Philip,
If you want to give the Weld-on a shot [i've fixed broken skimmers that i've received in the past this way as suggested] and then we'll see what UPS can do, that'd be great. I don't want you to feel like you've been screwed on this purchase!
I specified to the UPS rep that I wanted it packed with lots of packing material so that it would not break during transit, and had them pack it for me. I am not positive of insurance/covered amounts on the shipment but we'll see what they say about it.
The skimmer works great, and was not finicky at all for me so I'd highly recommend at least trying to weld the acrylic back together in order to use the skimmer.
Edit: Similar to USPS, UPS has an automatic $100 shipping insurance on every shipment [according to their website]
Since you paid $110 for it, i'd claim for the entire $100. I was not asked about additional insurance, and didn't think to add any additional, so the $100 would be it. If we're able to get that payment from UPS, i'd be happy to pass that on to you and you could keep the skimmer and fix it if you'd like.