There are no canonical answer to your question in the 5e range of products. There may be something to be found in the Gord the Rogue series by Gary Gygax as Pelor is a Greyhawk deity but that is a lot of research that involve books that are mostly out of print.
What I recommend instead it to look towards Fantasy Live Action Roleplaying Games that use boffer weapons. The one I played, NERO LARP, the mechanic for spell casting was to say the incant and then touch or hit a person with a soft seed filled packet.
You can download their rule book from their website.
I call upon the Earth to Cure Light Wounds
With Eldritch Force I build a Mystic Lock
I call forth a Magic Missile.
etc. They are found on page 66.
Solar is another boffer fantasy LARP with their rulebook on line. The spells start on Page 57.
To keep it manageable I would develop a phrase for each of the school of magic with a spot where you fill in the spell name. Then develop variations over time. For example Cure Wounds is a evocation spell so you say for all evocation spells "I call upon the Light to (spell name)". I call upon the Light to Cure Wounds.
Both NERO, Solar, and many other LARPS have been around a while. Because of this, the phrase mechanic has had a lot of playtesting behind it.