Buying individual stamps or stamp setsFirst, let me remark that I collect these stamps in unmounted (never hinged) mint condition.
Stampworld.com lists the 1925 and 1934 stamps as separate stamps. Looking at Delcampe listings, I am guessing Yvert & Tellier does this as well. I, always, found Stampworld.com mirrored Michel listings. Michel also tends to list stamps in order of their appearance. According to Stampworld.com, the 'value' of the full set lies with the two stamps issued in 1934. It quotes the value of the two stamps as € 27. It quotes the value of the eight stamps issued in 1925 as € 14. Of these, the stamp with the highest value is the 75 centimes stamp. This is quoted as being worth € 4. The second highest quote is for the 1 Franc stamp at € 2.50.
Having the 75 centimes, 90 centimes, and 1 Franc 50 centimes stamps in my collection, what would be the best way forward? Mostly British, French, Spanish, and Italian sellers offer the Morocco Agencies stamps on
eBay or Delcampe. French, Spanish, and Italian sellers may follow the Yvert & Tellier or Michel listings. So, they may offer the 1925 stamps separately. But will you, actually, get the correct set of stamps? I am not convinced you will.
I find sellers from these countries rarely state the watermark or show the back of the stamps. I contacted some that did not know there exist two watermarks. I, frequently, see that where the seller posts a picture of the back of the stamp, the watermark is not the one mentioned in the listing. I have seen listings of more than one stamp that mixed the watermarks.
US sellers even tend to be worse, struggling to identify the typography and photogravure issues correctly. I have seen quite a few listings of sets or part sets of Morocco Agencies stamps that had the key value typography stamp substituted for by the corresponding, almost valueless photogravure stamp. Yet the sellers offered these as full sets asking a price far above catalogue value of the actual stamps on offer.
Where there is no doubt about the identification, most stamps offered are those with the 'Simple Cypher' watermark. Other than that, I could not find a complete set of the 1925 stamps offered as such in unmounted mint condition on
eBay or Delcampe.
Last year, I did come across a few 1 Franc stamps with the 'Block Cypher' watermark. The cheapest listing was for the 75 centimes and 1 Franc stamps. This showed the back of the stamps. The 1 Franc looked very good; the 75 centimes appeared to have a small blemish. Since, already, I had the 75 centimes stamp and the two stamps were the cheapest I had seen the 1 Franc, I bought these.

To be honest, the 75 centimes stamp is quite fine. I, however, do prefer the one I already had.
Four down, six to go.
I am going further down the hole. With every stamp that holds very little value, I also must pay postage. This is starting to add. At the same time, buying a full set of the 1925 stamps is starting to be a waste of money. Based on the Stampworld.com quotes, I have € 6 out of € 14 worth of stamps in my collection. Another issue is that I did not see any on offer.