Since you want to use the system only in the winter time, why not just put the panels on the wall or at least close to 90 deg. If you use glycol, it will not get hot enough in the summer to degrade it too much and you can run straight from the panels to the floor.
I have been using a lot of these pumps lately, run from a 20w PV panel. No other controller necessary except for an internal t-stat.
Thermo Dynamics Ltd. - Solar Pumps