A Soviet allocation in the 1930s naval treaties

What tonnage allocation might the Soviet Union receive if invited into the 1930s naval treaties?

Probably an allocation comparable to France or Italy, which would in turn encourage Japan to demand more tonnage.

A hypothetical Soviet allocation would probably sit alongside those of France and Italy rather than Japan. Adding another navy at that level would change the rest of the treaty balance. Japan would likely demand more tonnage in response and cite the Soviet allowance as justification. Admitting another power could reopen the wider bargaining over ratios instead of merely adding one new quota.