hello-- Please take a moment to advise a newcomer about a used portrait lens for a 4x5 Speed. The key to this is my current 'budget' status. That noted, the 'Aero-Ektar' option is lost to me. However, what with the fp shutter it may be the case that a relatively less expensive barrel lens may be a workable solution. But which make, what size, and which reliable vendor? Does anything come to mind in the $200-300 range? thank you! ps: I'm told that a lens approaching ~300mm is what is often used (at least 1.5 times the camera's "normal" lens).