Of those, only the razor stamped "6 {peppercorn symbol} Z" is likely to be Sheffield-made. Probably 1760-1770.
Unfortunately, pipe marks were
extremely common, varied, and international. My guess is that the pipe marked razor and the ivory scaled razor with the crown and PM were both made in Sweden around 1780, but the PM razor is so strange I have little confidence. Maybe it was German? Probably not French.
However, the 'VIA' razor probably
is French, and I would guess late 1700's to early 1800's. OR, if the tail has a distinct 'trigger' shape, probably London made around the same time frame.
For English razors, we rely almost entirely on published directories for information. Of the 4 known directories published before 1800, only one is easily available (Gales & Martin, which you can find on
Google Books here -- this is a scanned copy of the 1887 reprinted edition, which includes a preface that's full of useful information). That was published in 1787 and some of the marks it collects went back a ways and others were newer.
The one directory prior to that was Sketchley's, from 1774.
To the best of my knowledge, there are no easily available copies of it. I have photographs of the two pages dedicated to razors, but often manufacturers made multiple types of goods and were not always listed where you'd think to find them. Marks like "6{peppercorn}Z" were typical of file makers and scissorsmiths, but they were used on all sorts of steel goods.
And that brings us around to two separate but related problems with Sketchley's.
First, the marks it recorded were often
wrong. Ann Rowland's mark is listed in Sketchley's as a"R {heart} AIN". Her mark was actually "R {heart} SPAIN". I've seen numerous others from Sketchley's that are similarly misprinted or just wrong.
Second, there's no way to search for symbols other than just reading through the whole work, and when those symbols are often misrepresented, matters get especially difficult.
Supposedly there is a 1737 Sheffield directory, but no one in Sheffield had seen it at the time of the reprinting of Gales & Martin and to the best of my knowledge it has never come to light.
There are, of course, also the Cutler's Company's records of apprentices and masters, but those don't include marks. And while Volume II of the History does include a scant few very early cutlers marks, it doesn't have a comprehensive listing. Volume I (which isn't available in scanned form), is mostly a narrative of the Company's history, and I haven't had a chance to get my physical copy restored in order to safely read it.
Without knowing the city of origin, I'm afraid old razors like these will remain a mystery.