Do you mean the price in 1920 against the price in 1934 or the price in 1933 against the price in 1934? If the latter, I see no reason to assume that the price would rise off hand. It would be determined by a combination of two effects: increased supply would yield cheaper alcohol, increased demand would yield pricier alcohol. If anything, I'm tempted to say that the former would predominate, but I don't (yet) have a source for this claim. I'll do my best to find the data, though, and edit this post

EDIT: I have found a good paper dealing with this, and more so, the related issue of consumption during Prohibition. Alcohol Consumption During Prohibition, Miron and Zweibel.

Miron and Zweibel come to the conclusion, using statistical analysis of such data as cirrhosis rates, that alcohol consumption dropped to approx. 30% of pre-Prohibition rates immediately following Amendment XVIII, and rose in the next several years to 60-70% of pre-Prohibition rates. Following Amendment XXI, consumption rates stayed about the same, and would reach the pre-Prohibition levels somewhere in the following decade. This leads credence to the idea that increased demand would not have increased the price of alcohol directly, and the lack of a need for the high search costs of finding a speakeasy and the high costs of doing business illegally, which would drive down prices (though, of course, the new excise taxes, and improved liquor quality, could also provide upwards support to prices). The authors of the paper discuss their findings that alcohol was roughly 3 times pricier in 1930 as it was before Prohibition. They do not, however, provide any research suggesting a post-Prohibition price, though I believe it likely that it would be lower than the price immediately before repeal for the stated reasons.