None I'm aware of, but the originals are simple enough. Each are cab height 3/4" plywood [no void preferred in HIFI/HT apps] and 10" wide framed with 2x2s with a single brace across the middle, though back then they really were 2x2s, so I recommend 2x3s. There were no triangulating braces like on the larger 210s because they were designed to be tied together with a pair of top baffles, so I recommend adding them plus using two cross braces.
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