You have Firing Line there in Aurora, Green Mountain Gun's (not the range), 5280 Armory in Arvada, and of course Jensen's Arms in Loveland. Bit of a drive, but the best prices i'm aware of at a brick and mortar. Between those shops, you're not gonna see much of a difference in price, but best to call first.
You can also contact Dave at
Protektsolutions. He's a one man show out of his home in Westminster, and a great guy to deal with. I got my first G19 from him and wouldn't look elsewhere for a Glock. He's also a member here on the forums. I referred another member to him and he was happy with his transaction as well.