Another one that looks good for the money is
http://www.grasscity.com/us_en/scientific-glass-bubbler-with-cage-perc.html#.ViSsK34rLIU
I've had one of these for about 3 years now. I bought mine for about $110 in Norway. It's got practically no restriction at all, so it pairs very well with the Solo. Out of all my 40 or so pieces, this is the one i use the most with my Solo.