It's how long is a piece of string time.
I reckon you should be abel to knock pretty big chunks off those times if you keep training consistently & are prepared to hurt yourself in races.
You are at an age where it is just starting to become an issue - i.e. it will be becoming very slightly harder to reach the same time as when you were in your twenties, but the biggest thing by far is the effect of training. If you look at races, you'll see that guys well into their 40's and even 50's are very often up at the sharp end, sometimes even winning them. I've just turned 41, and restarted running in earnest a year ago. Did 46 mins for 10k at New Year, 42:25 at Easter and now hoping for a sub-40 in the next few weeks (the big aim I have been working towards).
How low your times will go is anyone's guess really, there are so many factors. Your own physiology for a start, how much time you are prepared to give to training, how hard you are prepared to work, the quality of your training, your ability to stay injury free etc.
It's often a good idea to have some more long-term goals, and so shorter term ones which are stepping stones along the way. I'd suggest that a longer term goal of sub 50 minutes for 10k within a year or two would be feasible, and aim to have cracked the hour by say Easter. As you hit or miss the shorter term targets you can adjust your longer term goals if they seem to be unreachable or too easy.
Remember it is not necessarily all about actually hitting your targets though. My sub-40 target is what kept me motivated and going out so that running has become a habit. I've lost 12kg, am much healthier than I was, approximately 10 mins quicker over 10k, and had a lot of enjoyment from running over the last year. Suddenly the difference of a few seconds over an arbitrary barrier doesn't seem so important.