I purchased the Aoyue 474++ several years ago from amazon when it was on a black friday deal for $99. I have never had a problem with the unit. Just make sure you clean out the spring and replace the filter regularly.
https://www.amazon.com/Aoyue-Digital-Desoldering-Station-Built/dp/B00ABJ4AEC/ref=mp_s_a_1_2
Don't buy replacement springs by Aoyue. They are $10 a piece. Buy the official Hakko springs. You get 10 in a pack for $15, and are better quality.
https://www.amazon.com/Hakko-A1030-Spring-Filter-802/dp/B000E9VCXG/ref=mp_s_a_1_28