About 5 years ago, I paid £300 to a dealer for a 4x5" Norma with standard and bag bellows and I think one panel. If anything, I would say prices have gone down a little since then. The Super Angulon probably has a dealer price of £300 minus £60 or so for a service. I personally like 135 mm lenses, they cover 4x5" at infinity with little or no movements and are handy for the studio for close-up work, but in the condition you describe the Symmar is virtually worthless - if the fungus is on a glass/air surface and has not yet caused pitting, it can be cleaned off at a certain cost, if the fungus is more advanced and has attacked the balsam holding groups of elements together, you could buy a lens in good order for less than the repair cost. The case if in good condition is very strong and protects the camera well but is very heavy - if you are young, you may be able to walk some distance using the shoulder straps attached to the case, at my age I wouldn't unless I really had to.
My best guess on price based on UK market - dealer price for outfit around £550 to 600, e-bay around £350 to £400. But this IS a guess! Only buy if condition is really excellent - a Sinar Norma in good order will withstand moderate use almost indefinitely and could be the last camera you will ever need to buy, which places the price in perspective.