A couple of days ago, I posted a very similar message on the LF forum and was directed here as a terrific resource. Accordingly, I'll also seek input from this fine group.

A little over a year ago I was in the process of starting an Aero Ektar Speed Graphic build when my wife experienced some life-threatening health problems. As a result, my "project" was derailed for a period of time. Things are back to a more normal status and I'm interested in getting my "project" going again. One of the positives that came from this delay was that I became aware of the opportunity a Speed Graphic gives me to use a variety of old lenses in addition to the Aero Ektar (i.e. Velostigmats, Petzval, Gasc & Charconnet, etc). Before I start looking for old lenses, I want/need to acquire a Speed Graphic to serve as the foundation. BTW, I intend to use the resulting camera/lens platform like any 4x5 LF view camera. Accordingly, I anticipate shooting from a tripod 99.9% of the time. I understand that a Speed Graphic does not provide all the movements of most modern view cameras and I'm OK with those limitations. Lastly, to avoid complicating the discussion, I'll avoid any "lens" questions at this stage.

I apologize for all that background and palavering. Here is my question. What should I be looking for in purchasing a solid Speed Graphic?

Any comments, suggestions or recommendations you can provide would be sincerely appreciated. Thank you.

I have some Pacemaker for sale, fully restaured and operational but I'm not in USA, I think tha it's possible to find somebody in US.
Good Luck.
Laurent

Welcome to Graflex.org.

Search the threads since others have talked about the Aero Ektar on a Speed Graphic.

Some others will jump in and help you.

The most commonly used version of Speed Graphic with the Aero Ektar is the 4x5 Pacemaker Speed Graphic http://graflex.org/speed-graphic/pacemaker-speed-graphic.html .
The introductory version was made from 1947 to 1954 and have a Kalart or Hugo Meyer side rangefinder. The later version has a top mounted Graphic rangefinder called Top Rangefinder Speed Graphic and was made from 1955 to 1970. An Anniversary Speed Graphic could be used also.
Anniversary Speed was made from 1940-1946. Available with Kalart and possibly a Hugo Meyer side rangefinder, a Graphic aka spring back, Graflok back as a retro fit, or a Graflex back.
Pacemaker Speed introduced with a Graphic back, may be retro fit with a Graflok, Graflex back was available as an option.
Graflok back introduced in 1949 became the standard back in 1950 or 1951.
Top RF Speed Graphic has a Graflok back.
The most desirable Speeds for your application are:
Anniversary Speed with Kalart rangefinder and Graflok back.
Pacemaker Speed with Kalart and Graflok back.
Usable Speeds are:
Anniversary with Kalart and Graphic back.
Pacemaker Speed with Kalart and Graphic back.
Top RF Speed if you plan to not use the rangefinder or spend a lot of time making a custom cam for the rangefinder to match your lens.

Skip any Speed with a Graflex back as it requires a special type film holder. Skip any Speed with a Hugo Meyer range finder as they were made for specific focal lengths and most likely will not adjust to the Aero Ektar.

There are currently a lot of Pacemaker Speed Graphics in 4x5 format on Ebay at collector prices. Ebay is one source, post the listing number if you have questions about one.
https://www.keh.com/ is a good source for Speeds although they don't always have them in stock.
http://www.pacificrimcamera.com/ is another potential source.