Iuse a place in Cali CustomAquatic.com relly nice people glad to help u out, i ordered VHO from them and a place in Ambler, PA, called Champion Lighting.com cool guys too..........
I know ChampLight has the mogual 250 i use the 6500 K Iwasaki from them, it even broke a weld drop poped off the socket and they sent me a new bulb a month or 2 later at no cost so always good peeps.....
but shop around u could get better deals just check the fine print.....on shipping .....
peace
mike
PS let me know if u come up with any one that has cheap prices on 250 6500 k loking for one even a 5500K using it for my macro groth......
TK