Tammi,
If your DH is "taken with this machine", I'm flat slobbering over it. That is a gorgeous haul if ever I saw one.
With all the Singers we have we don't have a single singer oil bottle. Nor do we have a Singer Slant Stitch button holler in the pink egg case.
The set up you have there is what I'd like to do with my 401A.
As far as buttons go, I've been sewing my own on for decades. I put 'em on so they don't, wont, can't come off. Seriously.
Joe