You can fix it yourself. Just need all the tools, gauges, and technical info. You can find it on the internet.
There is a company Park that sells lot of tools. As bikes change you will need to update to new tools. I've often had to make tools when they were not available.
Chain stretch tool. Chain checker.
8 Speed-1/2" x 3/32", pin length: 7.2mm
9 Speed-1/2" x 11⁄128", pin length: 6.6 mm
10 speed-1/2“ x 11/128“, pin length: 5.9 mm
If it tore up the cassette and chain ring you may have had a 9-10 on an 8 or 8 on a 9 or 10 depending on the wear. They are all 1/2 on center so you may have had a stretched chain. www.parktool.com/ www.parktool.com/product/chain-checker-cc-
| current weight: 192.0