美国采购需求：3FM7，6V7Ah，铅酸电池，可充电电池，电源，备用电池

I'm on the lookout for a replacement battery for my grandson's electric ride-on car. The current battery is a non-spillable type, and it fits a popular model designed for toddlers. It needs to be 6V and have around 7AH capacity for a 20-hour discharge time, ensuring it can provide good playtime without interruptions. Could you please let me know where I can purchase a new battery that meets these specifications? I'm particularly interested in reliable suppliers or any recommendations for suitable alternatives. Your guidance would be greatly appreciated, as I want to get my grandson back to enjoying his rides as soon as possible!