This looks like your pictured measure. Don’t remember where I got it but I don’t use it anymore. If you can’t find one you can have this one for $5 plus shipping. Probably cost $8 to ship it FedEx. Goes from 40 to 60 grains.
Gary
I have one of those I found at either TOW or somewhere similar. I love the elegance of it, and hate width of it. A bit narrow for pouring in the powder. I use my smallest mouthed horn on the bag with that measure.
I had picked one up at the Ft. Frederick Market Fair a few years ago but I don't remember the sutler that I got it from. I believe it was just under $20 and they were available in brass or steel with the steel one being more authentic.
Ft.Frederick market faire, Jason Gatliff on suttlers row ( the historical trekking mag. fella) I picked one up from him to measure loads for un-mentionable BP cartridges. they are accurate in measurements and not all that expensive. The opening on the measure works very well in cooperation with a drop tube, never used it for a BP muzzle loading rifle but I see no reason that it would be hard to charge the measure from the horn.