I've never seen it before and I've never thought of it. I can see how this could be a fun summer look!

Nice Ricoh - Ricoh had a long history of making watches and few know about them now. But any good watch service should be able to do the job. The service will likely cost more than the watch is worth but that doesn't matter especially when it is a family watch. I collect and service Ricohs and I know the movement well. But I have never serviced one for another person.

Most excellent

Oh looks like you scored a good one!!! General tips like taking a bunch of pictures as you take it apart and I always keep screws separated with the parts they came from because I can't keep track otherwise where they belong. More specific to the Ricoh auto movement: it has a single banking pin and there is a single hole in the pallet fork that the pin goes in. Assuming the watch is running ok now, take care not to bump/move that banking pin when cleaning etc. On dial side when you remove the day and date wheel, before you remove the plate that goes over everything take note there is a very small horseshoe looking spring that rests against the inside edge of that cover plate and pushes against the finger that rides the day wheel. The spring can be hard to see so don't miss it and when reassembling be sure the spring is not under the center plate when you put the plate on. Keyless works and date quick change button works have a few springs that can keep you on your toes. Again lots of pics so you know how they go and a piece of peg wood shaved to a flat edge and use that flat edge to hold the spring down while you bend the other end in place to prevent those suckers from flying. Happy to answer questions if you run into a question. Good luck!

I think the jubilee makes it GADA. Combined with the datejust you can wear it with sweatpants to a tux and everything in between and never change your watch. My opinion of course.

Pocket watch would look great with that!

Put that Datejust on a jubilee and there simply is no other watch.