Many flavor/fragrance companies carry benzaldehyde, either as benzaldehyde or as artificial oil of bitter almonds.There doesn't seem to be any problem ordering a small quantity of benzaldehyde from such companies. The natural oil of bitter almonds is far too expensive for my tastes.
According to Title 21 Code of Federal Regulations, section 1310.04, the reporting threshold for transactions of benzaldehyde is 4 kg per month (http://www.deadiversion.usdoj.gov/21cfr/cfr/1310/1310_04.htm (http://www.deadiversion.usdoj.gov/21cfr/cfr/1310/1310_04.htm)
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This link might help those interested in producing benzaldehyde:
Post 208702 (https://www.thevespiary.org/talk/index.php?topic=7285.msg20870200#msg20870200)
(Antoncho: "The easiest synth of benzaldehyde from toluene", Chemistry Discourse)
Read the whole thread, there are several methods for making benzaldehyde covered, there should be a way for everybody with serious ambitions.
The production of benzaldehyde by the chlorination of toluene to either benzylchloride or benzalchloride (and some benzotrichloride and ringchlorinated compounds) is not unproblematic as it requires the use of chlorine (not nice) and it seems not to be as easy as it sounds - some bees had no problems, some bees say this way is shit. Same for the chlorination after the Loomis patent using bleaching powder.
Anyways: If one decides to go for toluene chlorination he might consider to use the following method to convert benzyl AND benzalchloride to benzaldehyde in one easy step: Boiling the reaction products of the toluene chlorination with an aqueous solution of hexamine (solid camping fuel tablets) converts both - benzyl and benzalchloride into benzaldehyde (Sommelet reaction).