I believe two seperate purchases. Would be nice to see whats on top of both bass drums. As to the possibility of getting flat gray and speckled gray both in the same kit, Yes. The flat gray was phased out in late 67. Speckled gray was the new color.

Definitely possible.

You set looks to have 3 mounts on top of one bass drum, but I cant see them clearly enough to maybe determine that was original.

The 22 BD originally had a Swivo tom receiver mounted on the right, and a swivo receiver mounted front center.

I replaced the front center receiver with a knobby. Then I FOOLISHLY added a swivo receiver at the middle center to mount a single tom in a single bass set up. (I did this in 1978, before I knew what a vintage drum was.) Thus that BD is now in player's condition rather than collectable condition.

At least the added mount is Rogers,beautiful kit by the way,serial numbers are not definitive,but you could check them on the rogers forum,Rogers sometimes used different and altered paper tags,which could put serial numbers out of sequence but all your tags are holiday ,so the serial numbers might be close enough to make a more educated guess as to whether they came together.I think rogers serial numbers were more consistent than other drums of the era.You could also look at the Jollity drum farm site,he is very knowlegable about rogers and dating,and last I checked there was an interesting article on there about how retailers sold and ordered rogers,like selling single drums off a kit and reordering drums to recomplete the "donor" kit that was on the floor which could be the case with your kit.The most common 4 pc.set up at that time was 20,12,16, ,5 pc was 20 12 13 16, so I would think it more likely that the 13 and 22 or just the 22 would be add ons, but your interiors say other wise.