May two kinds of sus forks kasi, 24" and 26", most 24" mtb frames are suspension corrected specifically for 26" forks kahit na 24" lang yun frame, kasi mas maraming available nun.
In your case hanggat maari try mo makakuha ng 24" na sus forks, isa pa lang nakitang kong ganun, yun gamit ni reymond na nasa post ni tayloric above, marjocchi siya na pang 24 talaga, feel ko mas magandang fit to sa frame mo, kaso baka out of production na kasi walang demand.
An alternative would be 26" sus forks na naka lowered, pwede siguro hanggang 80 or 70mm para hindi naman masyadong magiba yun ride, that said, si monual may built dati na 24" haro bmx race frame with a 26" suspension forks, seems ok naman, naijujump nya rin sa maliit na launch ramp, anything from rst, zokee or argyle should be good, syempre maganda yun maagan, pero the lighter you get the more expensive naman hehe.
Price ng zokee dj2 dito sa pinas around 10 to 12k php, may nagsasabi maganda din daw suntour duro dj, pero wala pa kong nakitang matinding djer na gumamit nito kaya not sure about it's durability.
Btw, expect to add around 4 pounds to your bikes weight pag naka sus ka.