1987 Kentucky KM-1500 Needs New Tuners (machine heads) - Advice?

[FlabbyFabby]

I bought this wonderful, Japan made, mandolin a year ago, and feel very lucky to have gotten it. But alas, age is catching up to it and the original buttons on the tuning pegs are breaking, the machine heads are showing wear and my luthier is recommending thinking about getting whole new machine heads rather than just replacing the buttons. He can't find buttons to match the originals and is thinking that when considering cost, it probably makes sense to change the whole tuner stuff now rather then wait and do it piecemeal - buttons now, tuners later.
Since I know nothing about making mandolins, and have only played two years I'd love to hear what you'd suggest I do. If new tuners are the way to go which should I get? I totally appreciate the fact that this is a special mandolin but don't feel the need to keep it's specialness by using original parts. What I do care about is maintaining its great sound and quality.
Thanks for your feedback

[Folkmusician.com]

I would proceed with replacing just the buttons (unless there is a major issue with the current tuners). It takes a whole lot of use to wear out a good set of tuners. Odds are they just need a good cleaning.

And congrats on the new mandolin. Your 1500 is a great instrument!

[sgrexa]

If you do not mind black, I have a set of buttons that will likely fit. Send me a PM, if interested, the cost would be free as long as you live in the USA.

Sean

[GTison]

Here's a link to Siminoff's page with tuners. These should be the same. I believe they are Gotoh brand. The KM1500 should have "worm under post ." If you just want buttons that seems like it would require a luthier to replace them. That may be more trouble because back then they didn't have screw on buttons as I recall. Maybe yours do? I have an 84 KM1000 with a similar setup my tuners are OK not great but I don't think I'd spring for replacing them. I wonder why the buttons are cracking?
Link:http://parts.siminoff.net/machines.aspx