Yes/no. Short answer, no. No one has shrunk the Saw Viper rifle down to fit the figures.
Longer answer.
It is kind of sort of based on the M60-E3 with a scope which Marauder does make in scale (scope not included).
https://www.marauderinc.com/product-p/210001g.htmBut the US Military "S.A.W." designation is typically referring to either the M249 or the lighter Special Forces version MK46.
M249 -
https://www.marauderinc.com/product-p/210002.htmMK-46 with modular holes for additional scope and sites if you wanted -
https://www.marauderinc.com/product-p/800014.htm