Probably more important is how the wiring is ran. My 260 has a multi-function light on top of the mast with two wires and a ground wire. One is for the steaming light (forward only) and one is for the anchor light (both steaming light and anchor light are illuminated). If your anchor light and steaming light are two separate light fixtures, then you should find two wires (one for each). If you have one fixture, then you probably have one muti-line wire that connects to the fixture (as my 260 has). Figure that out first.
Next, you need to see how you light fixture is attached to the mast. I'm thinking regardless of whether you go with factory original or aftermarket, you need to see how the current light is attached to the mast and make sure you can remove the old light and attach the new one. On my boat, I had to manufacture (using that term loosely) better attachment.
Bottomline: You are probably going to have to go up once to see what you have and a second time to do the replacement. Just the way things go. One thing nice about a 260 is you can do all of that when the mast is lowered (bought a 12 foot ladder to paint the dinning room (15 foot ceilings) and now use the ladder most often to work on the top of my mast).