Well, depending on how early you mean...I'd would advise against them. The ESP 5's from the mid 80's had ridiculously narrow string spacing. It was before the 3/4" or 19mm spacing became standard. The pickups were not the greatest. ESP has come a long way since then.
Try before you buy, if you're comfortable with it, then go for it, I'm sure it can't be expensive.
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