I have gone a little farther since last time. The combination of Metol and ascorbic acid gives the same activity as Metol and sulfite if the pH is 8.7, according to Mees & James. You can get close to that by a simple combination of 8.5 grams Metol, 8.8 grams ascorbic acid, 4 grams of sodium hydroxide and 10 grams of borax in water to make a liter. You can replace both hydroxide and borax with 28 grams of sodium metaborate (Kodalk will do). This combination should be very active. You will probably want to dilute it 1:1.
The ascorbic acid could be replaced by sodium ascorbate, in which case cut the hydroxide in half. However much borax you put in will not give pH much higher than 9.2. As little as 4 grams will give pH about 9.2. Sodium ascorbate is close to neutral. Have fun.