You picked the one of the highest price Garmin's for cycling. There are other models of Garmin Edge with maps at lower prices. You can buy them direct from Garmin for about the same price any dealer can offer them at. But not all have maps if you go too cheap. But all will have features you might not want. Just ignore those, but you'll have them if you ever get interested in them. Be pretty sucky to buy a cheap GPS with few features or that doesn't last but 18 months and then have to fork over more money. Possibly winding up spending more over ten years on a cheapo unit than you would have if you'd just bought the more expensive Garmin that would probably last 10+ years or more.
There are lots of really good GPS cyclometers for cycling if you don't think you care for Garmin. Wahoo, Lezyne, Hammerhead Karoo and more.