@Drygulch I think your desire to preserve and use the brush is a grand idea! Good luck with the preservation!
Come to the thread to learn about a brush restore. Stay for the picture and story of a preserved toe. It's actually a cool story, but forgive me, this was my first thought.
Are you planning on re-knoting it or just stabilizing the handle. If you go for the re-knot there's a good chance you can get the top and bottom to separate making it easier to work with. I'd strip or sand the bottom down to wood and spray it with a similar color enamel, then buff the top out. Best to always use an appropriate respirator when working with these old handles there could be lead paint or asbestos in the glue or plastic. Better safe than sorry. Since it's an heirloom piece you may want to pick up a similar handle to practice on first. Good luck!
Yeah sorry...The toe thing got me to jump offsides. The brush is kinda cool looking as is. Put it in a block of resin!
I have been looking at various resins and epoxies. I am going to figure out a way to test it first on something else, but it seems like I might be able to coat the entire base in a clear epoxy. sand and profile it back to a brush handle, and then do a seal of some sort over it.
Just a thought, since I don't think it's been mentioned. Since the paint may contain lead, if you sand it, make sure to wear a filter mask.
I have a work bench in the house I use for a lot of this type of stuff. In addition to the mask, this one will be worked on outside.
The suggestions of using a poly or urethane would definitely work. One thing to consider is that even a high-end 'clear' poly or urethane will add a trace amount (or more) of yellowing. Clear is never truly clear, unless you are talking about a resin.
Me, I would just leave it alone. I would find any other shave gear he owned, and a photo of him. I would make a shadow box of this stuff, with a small typed card detailing his history, put inside the shadow box. Then, I would hang it proudly.