Based on this product's specifications, here are some alternatives and similar models
Brake pads Clarks for HAYES models (Sole, GX2, MX2, MX3, MX4) sintered metallic
Summary description:
Sintered metallic brake pads by Clarks designed for HAYES brake calipers including Sole, GX2, MX2, MX3 and MX4 models. These replacement pads use a sintered metallic compound for increased durability, consistent braking performance and improved heat resistance. Suitable for mountain and trail bikes where strong stopping power and pad life are required.