Rates are highly specific per individual and company. FWIW, I pay $215/mo. for $10K monthly benefit through Principal (Own Occupation/specialty-specific, 90 day waiting period, residual disability/recovery benefit, 3% COLA rider, and future benefit increase/benefit update riders.
While in residency, I had a policy with Ameritas for $5k benefit (similar definitions/riders) and that was $150/mo. I switched after fellowship because buying a new policy with Principal was nearly 20% cheaper than utilizing the increase option with my old policy. Part of the price difference was I qualified for a slightly larger discount by being associated with my fellowship institution vs my residency.
You should definitely dig through your current policy and understand it well. I would find an independent insurance agent who can help review your current policy and give quotes from the major companies who offer true own occupation definitions (such as Principal, Standard, Ameritas, MassMutual, Guardian). A recommended list of insurance agents who won't try to sell you garbage you don't need (i.e. whole/universal life insurance) can be found over at White Coat Investor blog > Recommended > Insurance agents.