Tonearm base for Denon DK300 plinth?


Hi.Does anybody know where to find a tonearm base for the DK300 plinth? The plinths I see have what looks like a tonearm for a 9'' arm (or sometimes a 9'' tonearm already mounted), so, obviously if you want to use a 10 or 12'' one you need a different base... that can't be found anywhere separately.

Thanks.
sanjuro_61
Hi.Thanks for the answer.
Actually I don't have it... yet. Before buying one I want to be sure if I can get a custom tonearm base first. The web you make reference is onlinemetals.com, am I right? It does look nice. I'm in Europe, BTW, so I'll also be looking for a more local site (you know, shipping and taxes...).Is a specific non-magnetic alloy necessary?

Non-magnetic for sure, but after that it's your choice.  However, aluminum or brass are the two best obvious choices, if you choose to use metal.  Machinists like to work with them, because they are relatively soft. And "On-line Metals" is a good source.
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Hi.Yes. I'm looking into it. I'm a bit more concerned about fitting. Sometimes it's quite difficult to find the required hole diameter for a tonearm. I know the DA-308 fits. I've seen pictures. The diameter for the DA-308 is 22 mm, so that's my reference for the moment.