My attempt at a late alpha mp5. Comes with sound, real model, and textures. Extract v_9mmar.mdl to models folder, and hks1,hks2,hks3 in the sound/weapons folder.
This is the real alpha mp5 model resized and shaped to make it look like the mp5 form the later versions of Half-Life Alpha. The image makes it look a bit squished and fat, test in model viewer or in-game for better results, it's the best I could do.