You may avoid hydroquinone by using sodium ascorbate in its place. Ascorbic acid or its isomer erythorbic acid plus sodium bicarbonate make sodium ascorbate. For each gram of sodium bicarbonate, add 4.4 grams of ascorbic acid and a small amount of water. Let the effervescence subside before you add the mixture to the developer. The ratio of bicarbonate to ascorbic acid is not critical and you may use 1/2 spoonful of the bicarbonate for each spoonful of the ascorbic acid.
In the recipe for D-72, you could simply add enough carbonate to neutralize the ascorbic acid, but still mix the acid and the carbonate in a small amount of water and let the effervescence subside before adding the other ingredience. The CO2 remaining in the mixture will reduce pH somewhat otherwise.
You may substitute an amount of phenidone equal to 1/10 the weight of the metol for the metol in the recipe.