Also you already know the most important things
Lasever is I think the best quality/price you can find for blue. But there is always better quality, for more expensive...
For the red I recommand MAxyz modules 225mW (or 2x 225mW), the beam divergeance and diameter are very good (important when mixing with other colors) and affordable...
For mixing colors, you need 2 dichro filters (1 reflect red 1 and reflect blue) with adjustable mounts.