Replacing/repairing an old Ritchey Logic headset

Hi, I decided to keep the Dyna-Tech and fix her up as my daily ride.
I'm not the most technical of people, I know how to take things apart and put them back together but I am not good with names, anyway.
Recently aquired a mid 90's Dyna-Tech and have noticed there is a lot of movement in the forks with the brake son, which I am assuming id the headset bearings, I have read a few other stories about these heaset being vulnerable to the ravages of time. Can anybody give me some advice with repairing/replacaing it? I have searched around for a new one but haven't been able to find one that is black and not a modern cartiridge style.
Oh yes this is annoying me, what is a quill stem? Is it what I have and what was on all old bikes? The threaded headset?
Thanks in advance.
PS: Am I safe riding the bike with a damaged headset? Its not majorly broken but I dont want to be bombing downhill and to have the bars come out in my hand

Hi

Personally I wouldn't ride it if the headset is too loose especially when a replacement is so cheap http://www.ebay.co.uk/itm/TH-Industires ... 4ac8f817e1

Secondly the picture below shows a Quill stem used on virtually all bikes until the mid 90's when they were pretty much superseded by the aheadset and ahead stem