Dean,
I think you will find that the regulars in and around Paris as of June 15th were personnel in depots as cadres and in battalions being formed for field service, not as complete battalions assigned to garrison duty. IIRC large numbers of depots had been concentrated near the capital, including the Guards. I seem to recall that there were at least 6 battalions of Guards in formation and one cavalry regiment (the new 2nd Chasseurs a Cheval) near completion, so that alone would be near 4000 men. If you had 500 men in each of 60 depots (numbers for illustration only) that would be 12,000 men. So finding 20,000 regulars or so in Paris would not be a surprise. Were they effective? By no means would they all be. Regards,
David