I realize this post is over 2 years old now and my friend doesn’t own a Mooney, but a different plane with the Hoskins strobe setup pictured above. Found this post via google looking for Hoskins strobe lens replacements after my friend’s lens cracked and yellowed over the years. The grimes nav light lenses are a perfect replacement. I don’t have a part number handy (couldn’t find one) but my friend bought some from this ebay listing: https://www.ebay.com/itm/Aircraft-Tail-Light-Position-Light-Lens-Grimes-Whelen-Etc-Best-Ship-First-/144237270490?mkcid=16&mkevt=1&_trksid=p2349624.m46890.l49286&mkrid=711-127632-2357-0
Wanted to pay it forward with the info…