Syria, French French Administration, Airmail, 1921 (Sep 21), cover from Aleppo to Alexandria bearing the 'O.M.F. Syrie" & Value on two lines - 1921' overprints on POSTE PAR AVION purple overprint on previous French stamps  franking includes gutter pair of 1Syrian piastre on 20c POSTE PAR AVION purple overprinted stamp, only 3 known on the cover. (Mi. 170; Yt. PA4; Sg.. 78),  also the 5pi on 1fr. and 10pi on 2fr. (Mi. 161-162, Yt. SY-FR 65-66, Sg. SY 75-76). All cancelled by ________
Arrival ALEP cds on back dated __________
Nice and very rare cover. Signed by Expert at bottom front - Brun. Estimate $500 - 750.  
_____It appears the 21 of 21 Sep has reversed numerals and the received mark is 13 Sep