G&G have shared details of their Type 64 Scope Mount:
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Add some variety to your Type 64 BR AEG by adding a scope mount. It is constructed out of heavy-duty aluminum and attaches easily to the receiver in seconds. A 1913 Picatinny rail on top provides enough space to add a long-range scope with two scope rings. Coming soon. Preorder with your local G&G Authorized Dealer.
G&G