Yamaha 103 serial number and parts?

[Tortuba]

Well, I have found my "Old Man" tuba.
It is a Yamaha 103 in great shape. The previous owner found it in a pawn shop nearly 20 years and I recently bought it from his estate.
The horn has the small pearl buttons, black printed logo on the bell and the original bulky wood case.
So, a couple of questions regarding this horn:
The serial number is 002193. I understand that Yamaha was not consistent with the serial numbers but can I assume that this horn is probably from the 70s?
Given its age, are parts (valve guides, springs) readily available?
Is there a soft gig bag for this size horn? I wanted something lighter in weight but the horn in the wood case weighs almost as much as my full size horn (PT1 stencil) in a gig bag.

TIA
Keith
Toronto

[Jesse Brook]

Yamaha serial numbers start at round numbers. If I decode yours roughly right, I'd put the age around 1977. Only small parts are available, like springs and water keys. If you need a valve, you're out of luck. The same goes for leadpipes, tuning slides, bells, branches, those screws that connect the horn together on later models, braces, valve buttons, or valve caps.