If you want to cut the flatwater, you can put-in the river at the bridge. As you come down the hill toward Parkdale and cross the bridge, pull off in a little pull-off on the right, not blocking the rancher access. Walk back along a fisherman made trail through sagebrush to the river. It's my preferred -500cfs put-in.
A far better take-out at this level is at Tunnel Drive.... It will cut 20-30 minutes of flatwater at this level. It's on river left directly after the pink house at the tail end of a bushy island on the left. There will be a small trail. Cross down the tracks 50 feet or so and cross the canal using a 12-15 inch wide walk bridge, up the small hill to the car. You miss that Canon City wave drop with this take-out, but it's not worth seeing for another 1000 cfs or so. No wave to surf anyway at this level...not even close.
To get there by car, just turn left on Tunnel Drive off highway 50 after the right-hand curve after the territorial prison as you are leaving Canon City. Follow to dead end, park on the left facing the river. If you find yourself driving up above and along the river dodging dog-walkers and bikes on the tunnel trail, back up...you went too far.