Yes but ...... if you buy a replacement from Harbor it will be the same low quality. There is a place near Big R on Gabel and another place just off Montana near LP Andersen Tire. Both of those places sell high quality valves and gauges. There are dozen of kinds and sizes so take the broken one with you.
Sorry I don't know the answer to that..I would think some one at the store would be able to help..
Yes, just buy a new regulator.
Probably...yes...but you might need to go to a big box store like Lowe's or Home Depot
Probably need more detail. Check at store
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