Pittsburgh's prevailing wage site contains a lot of helpful information, and it looks like you should be able to search or request prevailing wage rates from this page: Pittsburgh Prevailing Wages. Alternatively, asking the public agency in charge of the project should be able to provide prevailing wage rates or at least provide some guidance on how to obtain that information. Or, you can directly request the prevailing wage rates for a PA project, here: Prevailing Wage Rates Determination Request.
Ultimately, though, the prevailing wage rates should come directly from the source to ensure all requirements are met.