... or create our own so it won't be blocked in some countries on youtube.
I think, new music or not, gamblers will not care. Just show your presentation in a professional way. The current source link about some list you have there is already a good reference.
Since you have mentioned,
"create our own", I think that would the best idea. Meaning you are capable to do that.
Youtube is strict even you will put a
"No copyright infringement intended" or give credits on the caption. If you think you can deal with that, then good.
I think it is for the site's use not to be publish on youtube. He can acquire license for specific music. All he needs to do is to contact the recording company for the needed license so that he can use that music for his site.
There are 6 types of Music license, OP can pick among these types that fits his needs :
Synchronization License (Sync License)This method of licensing refers to music that is going to be paired with some form of visual media. It has a broad range of uses, including commercials, studio films, streaming advertisements, personal films, internal communications, and more.
Mechanical LicenseA mechanical license is needed for any physical reproduction of an artist’s work. Primarily this refers to the manufacturing of CDs or distribution of music in any tangible form. Artists, aka copyright holders, will have agreements with record labels, distributors, and publishers on the mechanical terms of their music, and are generally paid per-copy.
A mechanical license is also needed if you are planning on recording a cover song, even if only a portion of the original song is used. This also includes adding your own lyrics, re-mixing, or changing anything about the original recording that affects the overall integrity of the artists' composition.
Master LicenseMaster licenses are a bit more complex than most others, in that they’re similar to sync licenses but not quite as broad-ranging. A master right is held by the person who owns the recording of a song. The master license gives the user permission to use a pre-recorded version of a song in a visual or audio project, but does not allow a user to re-record a song for a project (i.e. to cover or edit a song). Generally a master license is issued in conjunction with a sync license.
Public Performance LicenseThis license is perhaps the most common form of music license issued today. While ‘performance’ may be a limiting term, it applies generally to any broadcast of an artist’s work. This includes businesses who play music in their store, jukeboxes, or any other form of public performance — all the way up to concerts. Performing rights organizations (PROs) such as BMI, SESAC, and ASCAP generally manage public performance licenses and issue music royalties to artists on a per-use basis.
Print Rights LicenseThis license refers to the physical copy of the sheet music that an artist has created. It’s needed when someone prints a sheet music compilation, or any time the sheet music of copyrighted work is reproduced.
Theatrical LicenseAlso a very specific form of written permission, theatrical licenses are very common in the theater industry. The license is required any time a copyrighted work is performed on-stage in front of an audience
Source: https://www.musicbed.com/knowledge-base/types-of-music-licenses/28