For an authentic LP Jr, you'd really need the three-on-a strip style tuners. The classic LP sunbursts ('58-'60) used single line Kluson tuners with rounded front and rear edges, so the Klusons are klosest to those (see what I did there?

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Also, I'd go for the slightly higher tuning ratio of the Klusons and their more ivory button colour, rather than the snot green of the Grovers.