a usefull info would be whether you prefer beams or graphics (could affect the choice of galvos and their cost)
another piece of usefull info could be whether you are comfortable with making your own red modules or you will buy ready made ones
i could say that since you go for a 1w total power, the 640nm HL6385DG red diodes (two or better three of them probably) will be a good and obvious choice. or, for a cheaper solution you could get a 660nm quad module
so, something around 250mw-400mw blue (you can have more from the same module with no riscs, just by turning a pot on the power supply), 250mw green - analogue modulation and then dichros, mounts, a case, galvos etc etc
800 to 1000 looks very feasible to me (maybe a bit extra for a dac and software, depending on what you purchase)
"its called character briggs..."