If you're looking for a compact dual SIM smartphone with mid-range specifications and a display size less than 6.0 inches, there are a few options within your budget of less than 10,000 PHP. Here are a couple of recommendations:
1. Xiaomi Redmi 9C - This device features a 6.53-inch HD+ display, which is slightly larger than what you mentioned, but it still falls in the mid-range compact category. It supports dual SIM functionality and comes with decent specifications, including a MediaTek Helio G35 processor, 2GB/3GB RAM, and a triple camera setup (13MP + 2MP + 2MP) for photography. The Redmi 9C is priced around 5,990 PHP.
2. Realme C3 - Another option is the Realme C3, which has a 6.5-inch HD+ display. It supports dual SIM and packs a MediaTek Helio G70 processor, 3GB/4GB RAM, and a dual-camera system (12MP + 2MP) on the back. The Realme C3 offers good performance for its price and is priced around 6,990 PHP.
These smartphones provide a balance between compactness and affordability while still offering mid-range specifications. However, do keep in mind that prices may vary depending on the country and availability. It's always recommended to check local retailers or online stores for the most accurate and up-to-date pricing information.