I really think that military uniforms are best left in their rightful place. Even if you successfully altered this Enlisted Marine Dress Blue Blouse and change the buttons it will still look like what it is- a modified military uniform, rather than a doublet made to wear with your kilt.

As a Marine, I would find it off-putting to run into a non-Marine wearing a Marine uniform, albeit modified, as part of civilian formal dress.

If you particularly like the styling of Marine Dress Blues I'd suggest a Kenmore Doublet. Same standing collar, single-breasted style, but a civilian garment designed to be worn with the kilt.