Try Mancini,summit,jegs,or some of the board members who sell parts.Someone other than comp has something in stock.With a hyd cam you won't need to adjust valves often.Set them once and forget.Just use some quality adjuster screws and nuts.
If the heads had been milled excessively you would have intake alignment issues.
Get an adjustable pushrod and measure the length you need and compare to what you have.
With the proper pushrods you should'nt need adjustable rockers.