The GBD 9438 was made in several versions. The early pipes were made in their St. Claude, France facility and are usually referred to as pre-Codogan. After 1981 Comoy and GBD manufacturing were combined in the London Comoy factory. Both versions carry the 9438 designations. In addition, the pre-Codogan versions were made in two forms, one for the English, American and Australian markets and featured a fishtail saddle bit. The second type were made for the French and Continental market and feature a short flat saddle bit and are stamped France on the stummel. The English versions come in a wide number grades, where the French versions in far fewer varieties. What a GBD 9438 is worth in the marketplace is driven by several factors, Grade, rarity, condition, type and if it is hallmarked. Some like the French version, Sauvage, will regularly sell in the $35-50 range. Others like hallmarked smooth finish pipes can sell for upwards of $150 and sometimes substantially more for pristine examples. Post-Codogan GBDs are not considered to be of the same quality as the St. Claude made pipes and usually sell for considerable less. Their saddle bits have flat sides which make it easy to distinguish them from earlier pipes. Examples of the various types can be seen on the GBD Collector's Thread. Hope that helps a little. It took me several years to sort the 9438 type out but once you understand the different periods then it becomes more an ability to recognize each type by sight.