I feel your pain. I am having an electrical problem in my port starting circuitry. Problem is I don't know if its the starter, solenoid, battery or the wiring between.
Its not funny but yes at least you know what needs to be addressed. I don't think I could hear a gunshot from the engine room when I fire up the old DD's. In fact I can barely hear the engine turn over when one is already running. Easiest thing for me is to have someone hang their head off the back and tell me when it fires up.
My starter quit on my '81 410 a couple months back, and rather than going through the pain and expense of replacing it, I took it off and had it rebuilt at a local starter/generator shop in town. Works perfectly now, and only cost me $90.
I thought about that especially after I saw the price of a new one. But unfortunately it was pretty well shot, I don't think it was rebuildable, or even enough to get my core charge back. The thing was so burnt that it stunk up the boat with that electrical fire smell just by sitting there, and that was even after being out on the aft deck for 2 weeks in the open air. The windings and brushes had pretty much become a solid mass, the grease in it combusted, it was really shot. I'm not kidding we ran the boat for 20-30 minutes with it engaged and didn't realize until it caught fire. I am really lucky it wasn't worse.