Search:

https://www.hornady.com/muzzleloading/pa-conical#!/

The cut away shroud versions are "comped" as opposed to ported. 2019 catalog has them NIB at 1100.00 I don't recall that any of the 445 SM were ported.

Thank you for the pictures and your write up!
Regards,
Wiley

No half cock, but you will want to get a bottle of finger print remover!

http://stevespages.com/ipb-iverjohnson-66.html

http://mobile.gunauction.com/search/mobile_displayitem.cfm?itemnum=10223293

Probably chambered for 38 Largo, same dimensions as 38 Spl but much more lightly loaded.

Check out Lancaster Howdah pistols, on line:
http://www.rockislandauction.com/viewitem/aid/53/lid/131

Remington makes a knurled and swaged lead bullet with a .454" diameter. Also the base is slightly cupped. You might try these for a better seal. I got mine at Midway

It does appear to be reblued. http://www.coltsmfg.com/CustomerServices/SerialNumberLookup.aspx suggests it was made in 1903. You have a BB so you can pick a value, I'd guess $300-350

http://www.lodgewood.com/
http://www.vtigunparts.com/

These fully lock up the cylinder when the trigger is fully back and the hammer is in the fired position.

You could use a flat surface with 200 grit or higher sand paper to flatten the back of the new grips