Very nice find! I paired mine with a BD mini-cap and used it in many vacations. It has made me many litres of coffee
I have a BD silent damper for an 8/svea. It will probably fit the 99. Might give it a try once I have checked the seals.
The 99 was my 1st stove. My fil gifted it to me, like new in box. Then I later found one at a local antique store for $35. Lucked out on both.